Gun protective device



1957 P. F. PETERSON GUN PROTECTIVE DEVICE 2 Sheets-Sheet l Fiied Aug. 11, 1955 FIG.3

INVHVTOR PAUL F. PETERSON ATTORNEY Aug. 6, 1957 P. F. PETERSON GUN PROTECTIVE DEVICE 2 Sheets-Sheet 2 Filed Aug. 11, 1955 INVENTOR.

PAUL F. PETERSON ATTORNEY GUN PROTECTIVE DEVICE Paul F. Peterson, Palos Verdes Estates, Calif., assignor to North American Aviation, Inc.

Application August 11, 1955, Serial No. 527,727

7 Claims. (Cl. 89-13) This invention pertains to a gun protective device and more particularly to a device for preventing jamming or explosion of an automatic revolver-type gun.

Revolver-type guns have been designed and are now coming into widespread use which have automatically operated rotary drums receiving the ammunition from a suitable ram arrangement and arranged to'fire at a high cyclic rate. Typically for such a gun the rotary drum is provided with several apertures for receiving cartridges of ammunition from the feed mechanism. Firing takes place at the appropriate position of revolution'when the aperture is in alignment with the gun barrel. Following this the shell cases are extracted so that the aperture is free again to receive a cartridge. However, with all known extracting means for removing the cartridge cases from the drum there will be an occasional instance where a case is not completely extracted from the gun but remains,projecting from the aperture after the ejection operation. If this situation is not alleviated the live ammunition will then be rammed on top of the partially extracted case which will either jam the gun or cause damage to the feeder mechanism, and in some instances can result in an explosion.

- By the provisions of this invention a mechanical means is provided which positively prevents drum rotation when a case has been only partially extracted, thereby shutting down the gun and preventing jamming, feeder damage or an explosion.

. It is accordingly an object of this invention to provide a means for protecting a revolver-type gun to prevent jamming, feeder damage or explosion thereof.

Another object of this invention is to provide a mechanical means of stopping a gun when a cartridge case has been only partially ejected.

A still further object of this invention is to provide a means of preventing gun rotation upon partial case ejection by a means characterized by reliability, ruggedness and simplicity.

These and other objects will become apparent from the following detailed description taken in connection with the accompanying drawings in which:

Fig. 1 is a top plan view of the aft portion of a revolvertype gun including portions of the rotating drum;

Fig; 2 is a fragmentary view illustrating the extractor in its retracted position adjacent the drum;

Fig. 3 is an end elevation of the arrangement of Fig. 1;

Fig. 4 is a side elevation of the arrangement of Fig. 3 but with the drum slightly rotated and the ammunition shown associated with the drum; and

Fig. 5 is a sectional view taken along line 5-5 of Fig. 1 but with the drum position of Fig. 4.

Referring to the drawings the aft portion of gun I is illustrated, this including fixed portions 2 which are suitably attached to the structure of the device with which the gun is to be associated. This may be, for example, portions of an aircraft fuselage which mount and support the gun. A shaft 3 extends longitudinally of the gun, the rearward end of which is suitably supported in fixed Patented Aug. 6, 1957 ice mounting bracket 4 suitably apertured to receive the shaft. The front portion of shaft 3 is also suitably mounted but not illustrated in the drawings. A drum 6 is carried by shaft 3 and it is rotatable about the axis thereof. For the gun illustrated in the drawings rotation of drum 6 will be clockwise from the positions of Figs. 3 and 5.

Five apertures 7, located on a common circumference around the axis of the drum, extend longitudinally therethrough. These apertures are dimensioned to receive cartridges 8 (see Figs. 3 and 4) for feeding the gun during its automatic operation. Apertures 7 are spaced in correlation with the operation of the gun for feeding, fir ing and extraction of the ammunition. Typically, the gun may be designed to feed ammunition into the drum by two stages of ram at positions A and B at which locations the cartridges are inserted into the drum. Thus for an individual aperture 7 the cartridge is rammed partially therein at position A, and further rotation of the aperture to B will enable the second stage of ram to drive the cartridge home. Following this the aperture will be rotated to the bottom position C which is in alignment with the barrel of the gun. At this position the cartridge is electrically fired and the empty shell case is then rotated to position D adjacent extractor 11. This member comprises a reciprocal flipper 12 having a curved end 13 adapted to fit within groove 14 at the aft end of cartridge case 9. Member 12 is mounted on shaft 15 and during an extracting operation will be reciprocated to the outer position such as illustrated in Fig. 1. This extracts the empty cartridge case from the ammunition-receiving aperture 7 of the drum. A spring 16 is provided which returns the member 12 to its position adjacent the drum following its extracting of the cartridge case. This position may be seen in the fragmentary showing of Fig. 2. This means that as the particular aperture 7 is further rotated back to position A it is free to receive a cartridge for repetition of the cycle.

However, with a gun of this type there are occasions when the extractor will fail to completely remove the case from an aperture 7 as the aperture passes position D. If live ammunition is subsequently rammed in on top of this partially extracted shell case at positions A and B it will either jam the gun, cause feeder damage or an explosion. According to the provisions of this invention a member 18 is added to the gun assembly which prevents rotation of the drum whenever a case is only partially extracted. This member is disposed along the the rear surface 19 of the drum with a central annular portion 20 received on shaft 3 between the end ofthe drum and bracket 4. A projection 22 extends from the central portion 20 passing upwardly and then laterally so as to avoid ramming stations A and B. The bottom portion 23 of the projection of member 18 engages in abutting relationship a fixed portion 24 of the gun. A bracket 25 is mounted on portion 24 of the gun by means of screw 26, and includes a flange 27 carrying a pin 28. 1Tie pin loosely fits within an aperture 2B ofthe member The upper intermediate portion of projection 22 includes an extending lip 30 which projects forwardly over annular bead 31 on the aft end of the drum. This lip is constructed with depending portion 32 adjacent the forward face of the bead as best seen in Fig. 4.

Also projecting from member 18 is a lug 33 which extends to the circle of rotation of the cartridges and is disposed adjacent station D of the extractor, between this station and the first ram position A.

The operation of the device may be seen by reference to Figs. 3 and 4. As seen in Fig. 4 a cartridge case 9 has failed to eject completely and is partially projecting from drum 6. As the drum rotates from the extracting position case 9 will be brought into abutting engagement with lug-33. This lug acts as a mechanical stop which prevents further rotation of the drum and thus halts the operation of the gun before any damage can result. The forceexerted by the drum is attempting to rotate case 9 will be taken by projection 22 on fixed portion.24of the gun, and by annular portion. 20" engaging shaft;- 3. Projection 22 is maintained at all timesin positionwith bottom portion 23 abutting the fixed portion ofthe gun by the drum, while forward pivotal movement is precluded by the locationof the member 18 adjacent rear face 19 of the drum. Axial movement fore and aftisprecluded by the rear face of the drum and the forward edge of bracket 4.

Removal of member 18 for service or clearing of the gun is easily effected without major disassembly of the gun components. When shaft 3 of the gun is removed, member 18 may be pivoted about pin 28 in a clockwise direction from the position shown in Figs. 3 and to a location where it is free of thedrum. This position is shown in phantom in Fig. 5. When the member 18 is in this position it may be slid forwardly so as to be free of pin 28 and is thus removed from the gun assembly.

From the foregoing it can be seen that the arrangement of this invention provides an improved means for preventing damage to a gun whereby it is impossible to rotate the gun so as to cause jamming or explosion from ramming a live cartridge into an aperture containing a partially extracted case. The device is simple in construction, rugged in design and easily installed and removed.

The foregoing detailed description is to be understood as given by way of illustration and example only, the spirit and scope of this invention being limited only by the appended claims.

I claim:

1. In combination with a gun having a rotatable drum provided with cartridge-receiving openings extending axially therethrough, and having an extractor means for axially removing cartridge cases from said openings at a predetermined rotational position, said openings being adapted to receive shells at a location remote from said position, a gun protective device comprising a loadassuming member adjacent said drum, said load-assuming member being fixed relative to said drum and including an interfering portion projecting between said extractor means and said shell receiving location, said interfering portion being positioned in juxtaposition with the end of said drum to engage a partially extracted cartridge case protruding from said drum, thereby to prevent further rotation of such a case with said drum and halting rotation of said drum.

2. In combination with a gun having a rotatable drum provided with cartridge-receiving openings extending axially therethrough and disposed on a common circumference, said openings being adapted to receive cartridges at fixed locations during a revolution thereof, and extractor means for removing cartridge cases from said openings at a fixed location remote from said firstly mentioned fixed locations, said drum being rotatable about a shaft, said gun having fixed non-rotatable portions, a device for protecting such a gun comprising, a single member having a central portion encircling said shaft means; a lug extending therefrom to a position adjacent said drum between said ejector means and said firstly mentioned fixed locations thereby to form an interfering means for engaging a partially extracted cartridge case projecting from said drum; and a projection A from said previously mentioned portions to a position of engagement with said fixed portions of said gun for positioning said member against rotation with said drum whereby when a partially extracted cartridge case engages said lug said cartridge case is prevented from further rotation and rotation of said drum is halted.

3. A device as recited in claim 2 in which said projection includes means engaging said drum for preventing pivotal movement of said member relative to said drum through an are at right angles to the direction of rotation of said drum thereby to stabilize said member relative to said drum.

4. A device as recited in claim 2 in which said projection is provided with an aperture therethrough, and including in addition bracket means on said fixed portions of said gun, a pin projecting axially from said bracket through said aperture for preventing rotation of said member in a direction opposite to the rotation of said drum while permitting removal of said projection from said pin means by axial movement of said projection relative to said pin means.

5. In combination with a gun having a drum provided with axially extending cartridge-receiving openings disposed about acomrnon circumference, a shaft for rotatably mounting said drum, and fixed non-rotatable portions, said openings being adapted to receive cartridges at a fixed rotational position, and extractor means remote from said cartridge receiving position for removing cartridge cases from said drum, a device for protecting said gun comprising a member having an annular portion encircling said shaft; a lug extending from said annular portion to a location adjacent said drum between said extractor means and said cartridge receiving position, positioned to engage a partially extracted cartridge cas projecting from said drum; and a projection from said annular portion to a position of engagement with fixed portions of said gun for cooperating. with said annular portion in preventing rotation of said lug relative to said gun in the direction of rotation of said drum whereby when said lug engages such a partially extracted cartridge case said cartridge case and said drum are prevented from further rotation.

6. A protective device for a gun having a drum provided with axially extending cartridge-receiving openings disposed about a common circumference, a mounting shaft rotatably carrying said drum, and extractor means at the rear face of said gun for removing cartridge cases from said drum, said openings being adapted to receive cartridges through said rear face at a fixed rotational position remote from said extractor said gun further including means spaced from said rear face of said drum for supporting said shaft, and having fixed non-rotatable portions, said device comprising a load assuming member, said load assuming member having an annular portioned encircling said shaft and disposed between said support means and said rear face of said drum; a projection from said annular portion extending to a position of engagement with fixed portions of said gun laterally displaced on said drum and remote from said cartridge receiving position for preventing rotation of said load assuming member in the direction of rotation of said drum; lip means extending forwardly from said projection and engaging portions of said drum for preventing pivotal movement of said load assuming member relative to said drum through a direction at right angles to the rotational movement of said drum; and lugmeans projecting from said load assuming member to a position adjacent said rear face of said drum and between said extractor and said cartridge receiving position for interferingly engaging a partially extracted cartridge case projecting from said drum and thereby precluding further rotation of said drum.

7. A device as recited in claim 6 including in addition a. bracket attached to said fixed portions of said gun, said bracket including a flange extending adjacent the side of 5 said projecting portion remote from said rear face of said References Cited in the file of this patent iifi liifiiiiiggiii i f cif f d ii UNITED STATES PATENTS 10 men mg n aper ure imension to loosely receive said pin for preventing movement of 2656635 steveqs et a1 1953 said load assuming member about said shaft in a direc- 5 2708803 schnelder May 1955 tion opposite from the direction of rotation of said drum. 

